1. Field of Invention
The present invention relates to microcircuits. Specifically, the present invention relates to systems and methods for minimizing the susceptibility of microcircuits to upsets.
2. Description of the Related Art
It has been found that certain environmental conditions can increase the propensity of microcircuits to upsets of operation. The term “upset” refers to an erroneous change in the state of one or more storage elements in a digital system. A storage element is a circuit device that holds digital information for future processing. Storage element errors will propagate through subsequent logic and storage elements causing a failure of operation. Upsets are caused by erroneous insertion of positive and negative charges into the digital circuitry by several mechanisms, the most important being electromagnetic and nuclear radiation.
For particular applications, such as operating on-board spacecraft, digital systems are especially prone to upset, due exposure to high levels of radiation. Components used in these environments are typically specified with an upset rating in upsets/storage bit/day. Parts with low upset specifications tend to be more costly and to offer lower performance than conventional digital devices. To date the principal methods of counteracting upsets are to: provide low-upset components, provide redundancy, or (if radiation is the cause of the upsets) harden or shield the affected components. Generally, these options increase the cost, weight and power consumption of the system. This is a general problem in an industry that is constantly striving to provide smaller, more powerful microprocessors with lower power consumption, and is especially critical in spacecraft and aircraft applications.
Hence, a need remains in the art for a system and method for maintaining the upset rate of microcircuits within acceptable limits, while optimizing performance and minimizing power consumption.